Inhalator, a powder composition and a process for administering the powder composition using inhalators

ABSTRACT

An inhalator including an inhalator body including a powder receiving chamber for receiving a powder, an air-powder mixture reservoir for temporarily storing an air-powder mixture flowing from the powder receiving chamber, and a diluent air passage for introducing a diluent air into the air-powder mixture reservoir. The air-powder mixture is formed within the powder receiving chamber when an air is introduced into the powder receiving chamber. The air-powder mixture within the air-powder mixture reservoir is admixed with a diluent air introduced thereinto through the diluent air passage. The diluted air-powder mixture is discharged from an air-powder mixture outlet into a user&#39;s oral or nasal cavity. A powder composition for inhalators includes at least two kinds of fine particles different in particle diameter.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an inhalator suitable foradministering a powder or powder composition, and a powder compositioncontaining powders different in particle diameter from each other and aprocess for administering the powder composition using inhalators.

[0002] Generally, a powder inhalator is used for inhaling a powder orpowder composition such as a powdered medicine into a human body throughthe oral or nasal cavity. The inhalator includes an inhalator bodyhaving an air intake path for introducing an ambient air and a suctionopening through which an air-powder mixture within the inhalator body issucked into the oral or nasal cavity. A powder receiving chamber forreceiving the powder is disposed within the inhalator body andcommunicated with the outside of the inhalator body via the air intakepath. An air-powder mixture path extends from the powder receivingchamber to the suction opening. The air-powder mixture is formed whenthe air is introduced into the powder receiving chamber through the airintake path. The air-powder mixture is then transmitted from the powderreceiving chamber to the suction opening via the air-powder mixturepath.

[0003] There are several types of powders different in aerodynamic meanparticle diameter as follows: a powder having the aerodynamic meanparticle diameter of not less than 7 μm and depositing in an oral cavityor hypoglottis, a powder having the aerodynamic mean particle diameterof 5-7 μm and depositing in a throat, a powder having the aerodynamicmean particle diameter of 3-3 μm and depositing in a trachea, a powderhaving the aerodynamic mean particle diameter of 1-3 μm and depositingin bronchi, and a powder having the aerodynamic mean particle diameterof not more than 1 μm and depositing into alveoli, and the like. Thepowder having the aerodynamic mean particle diameter of not more than 3μm is required to surely reach affected areas of the human body. Also,the powder such as an acrid powder is preferably dosed in several partsupon being inhaled.

[0004] In addition, there has been proposed powder tobacco for use withthe inhalator. The powder tobacco can be substituted for a usual smokingtobacco because the powder tobacco provides a smoking feeling upon beinginhaled. When the powder tobacco is used, one dose of the powder tobaccois dispensed in parts from the inhalator upon each inhalation.

[0005] The human bronchi and alveoli exist in deeper portions of thehuman body. Therefore, in order to ensure stable deposit of the powderhaving the particle diameter of not more than 3 μm in the bronchi andalveoli, it is preferable to dose the powder in parts, i.e., dispense asmall amount of the powder each inhalation.

[0006] However, in the earlier technique, the whole amount of the powderreceived within the powder receiving chamber of the inhalator isdispensed from the inhalator by the inhalation substantially at onetime. If a dose of the powder having the particle diameter of not morethan 3 μm is inhaled through the inhalator upon inhalation, a largeamount of the powder dosed will be deposited in the oral cavity ortrachea before being deposited in the bronchi and alveoli.

[0007] Further, there is known a process for administering a particulatemedicament having a specific mean particle diameter into a patient'slungs upon the patient breathing. International Publication No.WO97/36574 discloses a process and device for inhalation of particulatemedicament. The process includes (i) providing an inhalator whichcontains at least one dose of medicament particles comprising sphericalhollow particulates of respirable particle size suitable for depositionin a human lungs, and (ii) removing the spherical hollow particulatesfrom the inhalator. In the earlier technique, the particulate medicamenthaving the specific particle diameter is used with the inhalator, butthere is not described inhalation on multi-purpose prescription, forinstance, one-time inhalation of multiple particulate medicaments forthe purpose of simultaneous deposition in different portions such as thetrachea and the alveoli of the patient's body. In order to follow themulti-purpose prescription, it is required that the patient repeatedlyinhales separate doses of particulate medicaments for differentprescriptions, takes a specific particulate medicament formulated forthe multi-purpose prescription, or is treated with the combination ofvarious prescriptions including peroral medicament, injection,application of fomentation, and the like.

SUMMARY OF THE INVENTION

[0008] It is an object of the present invention to provide an inhalatorcapable of dispensing one dose of a powder or powder composition inparts therefrom.

[0009] It is another object of the present invention to provide a powdercomposition containing powders different in particle diameter from eachother and a process for administering the powder composition usinginhalators, which are suitable for simultaneous deposition in differentportions of the human body by one-time inhalation.

[0010] According to one aspect of the present invention, there isprovided an inhalator for administering an air-powder mixture,comprising:

[0011] an inhalator body including an air intake path for introducingair into the inhalator body, and an air-powder mixture outlet fordischarging the air-powder mixture from the inhalator body;

[0012] a powder receiving chamber adapted to receive a powder, thepowder receiving chamber being disposed within the inhalator body andcommunicated with an outside of the inhalator body through the airintake path;

[0013] an air-powder mixture path adapted to transmit the air-powdermixture flowing from the powder receiving chamber to the air-powdermixture outlet;

[0014] an air-powder mixture reservoir adapted to temporarily store theair-powder mixture flowing from the powder receiving chamber, theair-powder mixture reservoir being disposed within the air-powdermixture path; and

[0015] a diluent air passage adapted to introduce a diluent air into theair-powder mixture reservoir, the diluent air passage communicating theair-powder mixture reservoir with the outside of the inhalator body.

[0016] According to a further aspect of the present invention, there isprovided an inhalator for administering an air-powder mixture,comprising:

[0017] a casing including an air intake inlet for introducing air intothe casing, and an air-powder mixture outlet for discharging theair-powder mixture from the casing;

[0018] powder receiving means for receiving a powder within the casingand permitting the powder to be admixed with the air introduced from theair intake inlet;

[0019] air-powder mixture storing means for temporarily storing theair-powder mixture passing through the powder receiving means;

[0020] diluent air passage means for permitting a diluent air to flowinto the air-powder mixture storing means; and

[0021] air-powder mixture path means for permitting the air-powdermixture to flow from the powder receiving means to the air-powdermixture outlet via the air-powder mixture storing means.

[0022] According to another aspect of the present invention, there isprovided a powder composition for use with an inhalator, comprising:

[0023] at least two kinds of fine particles selected from a first kindof fine particles having an aerodynamic mean particle diameter of notless than 7 μm, a second kind of fine particles having an aerodynamicmean particle diameter of 5-7 μm, a third kind of fine particles havingan aerodynamic mean particle diameter of 3-3 μm, a fourth kind of fineparticles having an aerodynamic mean particle diameter of 1-3 μm, and afifth kind of fine particles having an aerodynamic mean particlediameter of not more than 1 μm.

[0024] According to a further aspect of the present invention, there isprovided a process for administering a powder composition using aninhalator, comprising:

[0025] preparing the powder composition containing at least two kinds offine particles selected from a first kind of fine particles having anaerodynamic mean particle diameter of not less than 7 μm, a second kindof fine particles having an aerodynamic mean particle diameter of 5-7μm, a third kind of fine particles having an aerodynamic mean particlediameter of 3-3 μm, a fourth kind of fine particles having anaerodynamic mean particle diameter of 1-3 μm, and a fifth kind of fineparticles having an aerodynamic mean particle diameter of not more than1 μm;

[0026] supplying the powder composition to the inhalator; and

[0027] discharging the powder composition from the inhalator.

[0028] The other objects and features of this invention will becomeunderstood from the following description with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029]FIG. 1 is an elevation of an inhalator of a preferred embodiment,according to the present invention;

[0030]FIG. 2 is a longitudinal section of the inhalator, taken along theline 2-2 of FIG. 1, showing a rest position of the inhalator;

[0031]FIG. 3 is an enlarged section of the inhalator, taken along theline 3-3 of FIG. 2;

[0032]FIG. 4 is an enlarged section of the inhalator, taken along theline 4-4 of FIG. 2;

[0033]FIG. 5 is an enlarged section of the inhalator, taken along theline 5-5 of FIG. 2; and

[0034]FIG. 6 is a view similar to FIG. 2, but showing a use position ofthe inhalator.

DETAILED DESCRIPTION OF THE INVENTION

[0035] Referring to FIGS. 1-6, an inhalator, according to the presentinvention, of a preferred embodiment is explained.

[0036] As illustrated in FIG. 1, the inhalator includes an inhalatorbody 1 as a casing which is formed into a cylindrical shape. Inhalatorbody 1 is made of a suitable resin material such as polypropylene,polystyrene, ABS resin and the like. Inhalator body 1 is constituted ofcap 3, suction body 4 and capsule body 2 interposed between cap 3 andsuction body 4. Cap 3 has air intake inlet 7A shown in FIG. 2, throughwhich an ambient air is introduced into cap 3 and flows toward capsulebody 2 and suction body 4 as explained later. Cap 3 has a length shorterthan that of capsule body 2 and is rotatably connected with an upstreamside of capsule body 2. Suction body 4 has air-powder mixture outlet 18shown in FIG. 2, from which an air-powder mixture formed in inhalatorbody 1 is discharged into a user's oral cavity. Suction body 4 has alength longer than that of capsule body 2 and is rotatably connectedwith a downstream side of capsule body 2.

[0037] As illustrated in FIG. 2, capsule body 2 has engaging projection2A and engaging groove 2A1 on the upstream end portion. Engagingprojection 2A and engaging groove 2A1 axially adjacent thereto areengaged with engaging tube portion 3A and engaging projection 3A1 of cap3, respectively. Capsule body 2 is coupled with cap 3 by the engagementof engaging projection 2A and engaging groove 2A1 with engaging tubeportion 3A and engaging projection 3A1, respectively. Capsule body 2also has at the downstream end portion, engaging projection 2B andengaging groove 2B1 axially adjacent thereto. Engaging projection 2B andengaging groove 2B1 are engaged with engaging tube portion 4A andengaging projection 4A1 of suction body 4, respectively. Capsule body 2is coupled with suction body 4 by the engagement of engaging projection2B and engaging groove 2B1 with engaging tube portion 4A and engagingprojection 4A1, respectively.

[0038] Cocoon-shaped powder receiving chamber 5 is substantiallycoaxially disposed within capsule body 2. Powder receiving chamber 5 isprovided for receiving a dose of a powder or powder composition such asparticulate medicament, powder tobacco or the like. Powder receivingchamber 5 is in communication with the outside of inhalator body 1through air intake path 6, when the inhalator is in a use position asexplained later by referring to FIG. 6. The air-powder mixture is formedwithin powder receiving chamber 5 when the air flows into powderreceiving chamber 5 via air intake path 6 in the use position of theinhalator.

[0039] Air intake path 6 is provided for introducing the air into powderreceiving chamber 5. Air intake path 6 includes upstream intake passage7 formed in cap 3 and downstream intake passage 8 formed in capsule body2. Upstream intake passage 7 has an upstream end opening as air intakeinlet 7A which is open to a generally central portion of an axial endface of cap 3. Upstream intake passage 7 has a downstream end openingthat is open to a bottom of engaging tube portion 3A which mates with anaxial end face of engaging projection 2A, in an offset position relativeto the center axis of cap 3. Downstream intake passage 8 has an upstreamend opening that is open to the axial end face of engaging projection 2Ain an offset position relative to the center axis of capsule body 2.Downstream intake passage 8 has a downstream end opening that is open toan upstream end portion of powder receiving chamber 5 and insubstantially alignment with the center axis of capsule body 2.

[0040] Capsule body 2 and cap 3 are relatively rotatable to be placed ina non-communication position shown in FIG. 2 and a communicationposition shown in FIG. 6. In the non-communication position, thedownstream end opening of upstream intake passage 7 and the upstream endopening of downstream intake passage 8 are out of alignment with eachother. Fluid communication between upstream intake passage 7 anddownstream intake passage 8 is blocked so that powder receiving chamber5 is prevented from being fluidly communicated with the outside of theinhalator. On the other hand, in the communication position, thedownstream end opening of upstream intake passage 7 and the upstream endopening of downstream intake passage 8 are in alignment with each other.The fluid communication between upstream intake passage 7 and downstreamintake passage 8 is established so that powder receiving chamber 5 isfluidly communicated with the outside of the inhalator. The opening areaat the connection of upstream intake passage 7 and downstream intakepassage 8 may be desirably regulated by adjusting the alignment ofintake passages 7 and 8 to thereby control a flow amount of the airintroduced into powder receiving chamber 5 and therefore control anamount of the powder in the air-powder mixture flowing from powderreceiving chamber 5 toward air-powder mixture outlet 18.

[0041] Air-powder mixture path 9 extends between powder receivingchamber 5 and air-powder mixture outlet 18. Air-powder mixture path 9permits the air-powder mixture to flow from powder receiving chamber 5to air-powder mixture outlet 18 when the inhalator is in the useposition.

[0042] First air-powder mixture reservoir 12 is disposed withinair-powder mixture path 9. Air-powder mixture reservoir 12 is disposedin substantially coaxial with suction body 4. Air-powder mixturereservoir 12 is adapted to be communicated with powder receiving chamber5 through discharge passage 10 and connecting passage 11 of air-powdermixture path 9. Air-powder mixture reservoir 12 has a cocoon shapehaving a volumetric capacity greater than a volumetric capacity ofconnecting passage 11. Air-powder mixture reservoir 12 having thegreater volumetric capacity allows the air-powder mixture flowingthereinto through connecting passage 11 to be temporarily stored.

[0043] Discharge passage 10 is formed in capsule body 2 so as to be opento powder receiving chamber 5 at the upstream end and to engagingprojection 2B at the downstream end. An upstream end opening ofdischarge passage 10 is open to a downstream end portion of powderreceiving chamber 5 and in substantially alignment with the center axisof capsule body 2. A downstream end opening of discharge passage 10 isopen to an axial end face of engaging projection 2B in an offsetposition relative to the center axis of capsule body 2. Connectingpassage 11 is formed in suction body 4 so as to be open to engaging tubeportion 4A at the upstream end and to air-powder mixture reservoir 12 atthe downstream end. An upstream end opening of connecting passage 11 isopen to a bottom of engaging tube portion 4A which mates with the axialend face of engaging projection 2B, in an offset position relative tothe center axis of suction body 4. A downstream end opening ofconnecting passage 11 is open to an upstream end portion of air-powdermixture reservoir 12 and in substantially alignment with the center axisof suction body 4. Capsule body 2 and suction body 4 are relativelyrotatable so as to be placed in a non-communication position shown inFIG. 2 and a communication position shown in FIG. 6. In thenon-communication position, the downstream end opening of dischargepassage 10 and the upstream end opening of connecting passage 11 are outof alignment with each other so that fluid communication betweendischarge passage 10 and connecting passage 11 is blocked. Powderreceiving chamber 5 is prevented from being fluidly communicated withair-powder mixture reservoir 12. On the contrary, in the communicationposition, the downstream end opening of discharge passage 10 and theupstream end opening of connecting passage 11 are in alignment with eachother. The fluid communication between discharge passage 10 andconnecting passage 11 is established so that powder receiving chamber 5is fluidly communicated with the air-powder mixture reservoir 12. Theopening area at the connection of discharge passage 10 and connectingpassage 11 may be desirably regulated by adjusting the alignment ofdischarge passage 10 and connecting passage 11 to thereby control anamount of the air-powder mixture flowing from powder receiving chamber 5into air-powder mixture reservoir 12.

[0044] First diluent air passage 19 is formed in suction body 4 andcommunicated with air-powder mixture reservoir 12. Diluent air passage19 introduces a diluent air into air-powder mixture reservoir 12 whenthe air-powder mixture flows from powder receiving chamber 5 intoair-powder mixture reservoir 12. The diluent air introduced is merged inthe air-powder mixture within air-powder mixture reservoir 12 to therebydilute the air-powder mixture. The diluted air-powder mixture flowingfrom air-powder mixture reservoir 12 has a reduced flow rate and adecreased mixing ratio of the powder relative to the air which arepresent in the diluted air-powder mixture. Diluent air passage 19 isconstituted of four passages arranged in crossed manner in lateralsection in this embodiment as shown in FIG. 3. As illustrated in FIG. 3,each of four diluent air passages 19 has an inlet open to an outercircumferential surface of suction body 4 and an outlet open to acircumferential surface of air-powder mixture reservoir 12.

[0045] Second air-powder mixture reservoir 14 is disposed withinair-powder mixture path 9 downstream of first air-powder mixturereservoir 12. Air-powder mixture reservoir 14 is disposed insubstantially coaxial relation to suction body 4. Air-powder mixturereservoir 14 is communicated with air-powder mixture reservoir 12through communication passage 13 of connecting passage 11 which extendsin the axial direction of suction body 4. Air-powder mixture reservoir14 has a bell shape having a volumetric capacity greater than avolumetric capacity of communication passage 13 when viewed in axialcross-section. Air-powder mixture reservoir 14 with the greatervolumetric capacity allows the air-powder mixture flowing thereintothrough communication passage 13 to be temporarily stored.

[0046] Dispersion part 15 is disposed within air-powder mixture path 9downstream of second air-powder mixture reservoir 14. Dispersion part 15is adapted to prevent the powder in the air-powder mixture flowing fromsecond air-powder mixture reservoir 14 from aggregating together andintimately mix the powder and the air to form a uniform air-powdermixture. Dispersion part 15 includes dispersion chamber 17 and aplurality of dispersion passages 16 connected with dispersion chamber17. Dispersion passages 16, four passages in this embodiment, connectdispersion chamber 17 with air-powder mixture reservoir 14. Each ofdispersion passages 16 has an inlet open to air-powder mixture reservoir14 and an outlet open to dispersion chamber 17. Specifically, dispersionpassage 16 includes an inlet passage portion extending from an outerperipheral portion of air-powder mixture reservoir 14 in the axialdirection of suction body 4. Dispersion passage 16 also includes outletpassage portion 16A that radially inwardly extends from a downstreamside of the inlet passage portion and is open to an upstream end portionof dispersion chamber 17. As illustrated in FIG. 4, dispersion chamber17 has a generally circular-shaped section and outlet passage portion16A extends in a tangential direction of dispersion chamber 17. Theair-powder mixture flowing into dispersion chamber 17 through dispersionpassages 16 forms a swirl flow within dispersion chamber 17. The swirlflow of the air-powder mixture prevents the powder in the air-powdermixture from forming an aggregated mass of the powder.

[0047] Second diluent air passage 20 is formed within suction body 4 incommunication with dispersion chamber 17. As seen from FIGS. 2 and 5,four diluent air passages 20 radially extend from grooved portion 4B onan outer surface of suction body 4 to dispersion chamber 17. Groovedportion 4B extends along the entire circumference of the outer surfaceof suction body 4. Diluent air passages 20 introduce the ambient air asa diluent air into dispersion chamber 17 when the air-powder mixturewithin dispersion chamber 17 is directed toward outlet 18 by the user'ssuction.

[0048] Regulator 21 for variably controlling a flow amount of thediluent air introduced into dispersion chamber 17 via diluent airpassages 20 is axially moveably disposed on grooved portion 4B ofsuction body 4. Regulator 21 is in the form of a ring in thisembodiment. Regulator 21 has four regulator holes 21A coming intoalignment with diluent air passages 20 by the axial movement of theregulator 21. Regulator 21 variably regulates an opening area of each ofdiluent air passages 20 to thereby variably control the flow amount ofthe diluent air which is merged in the air-powder mixture withindispersion chamber 17.

[0049] The air-powder mixture passing through dispersion passages 16 anddispersion chamber 17 flows to air-powder mixture outlet 18 from whichthe air-powder mixture is dispensed into the user's oral cavity.Air-powder mixture outlet 18 is communicated with dispersion chamber 17and open to one axial end surface of suction body 4. Air-powder mixtureoutlet 18 is disposed substantially coaxially with the center axis ofsuction body 4.

[0050] Referring back to FIG. 1, counter or registration marks 22, 22,22 are formed on the upstream and downstream end portions of the outercircumferential surface of capsule body 2, downstream engaging tubeportion 3A of cap 3, and upstream engaging tube portion 4A of suctionbody 4, respectively. When counter mark 22 on the upstream-end side ofcapsule body 2 is aligned with counter mark 22 on the downstream-endside of cap 3, upstream and downstream intake passages 7 and 8 of airintake path 6 are communicated with each other. When counter mark 22 onthe downstream-end side of capsule body 2 is aligned with counter mark22 on the upstream-end side of suction body 4, discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 are communicated witheach other.

[0051] An operation of the thus-constructed inhalator of the presentinvention will be explained hereinafter.

[0052] When the inhalator is in a rest or nonuse position shown in FIG.2, upstream and downstream intake passages 7 and 8 of air intake path 6are fluidly disconnected from each other and discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 are fluidlydisconnected from each other. In this state, powder receiving chamber 5is prevented from being fluidly communicated with the outside ofinhalator body 1 and air-powder mixture reservoir 12. Thus, if theinhalator is in the rest position, the powder received within powderreceiving chamber 5 can be restrained from flowing therefrom andinhalator body 1 when the user carries the inhalator.

[0053] Next, upon using the inhalator, cap 3 and suction body 4 arerotated relative to capsule body 2 to align respective counter marks 22with each other. Regulator 21 is axially moved in grooved portion 4B soas to desirably adjust the opening area of second diluent air passage20. The inhalator is thus placed in a use position shown in FIG. 6. Inthe use position, upstream and downstream intake passages 7 and 8 of airintake path 6 are fluidly connected with each other and dischargepassage 10 and connecting passage 11 of air-powder mixture path 9 arefluidly connected with each other. Powder receiving chamber 5 is allowedto be in fluid communication with the outside of inhalator body 1 andair-powder mixture reservoir 12. In this state, air-powder mixtureoutlet 18 of inhalator body 1 is put into the user's oral cavity and theambient air is sucked by the user. The air is introduced into air intakepath 6 through air intake inlet 7A. The air then flows into powderreceiving chamber 5 as indicated by arrows in FIG. 6. The introduced airis admixed with the dose of the powder within powder receiving chamber5, forming the air-powder mixture. The air-powder mixture flows intofirst air-powder mixture reservoir 12 via discharge passage 10 andconnecting passage 11 of air-powder mixture path 9. The air-powdermixture is temporarily stored within air-powder mixture reservoir 12 andadmixed with the diluent air introduced through diluent air passage 19.The thus diluted air-powder mixture has a decreased flow rate flowinginto communication passage 13, and a reduced mixing ratio of the powderin the diluted air-powder mixture to the air in the diluted air-powdermixture.

[0054] The diluted air-powder mixture within first air-powder mixturereservoir 12 flows into second air-powder mixture reservoir 14 viacommunication passage 13 and then enters into dispersion chamber 17 viadispersion passages 16. There occurs a swirl flow of the dilutedair-powder mixture within dispersion chamber 17. The swirl flow atomizesan aggregated mass of the powder which remains in dispersion chamber 17,to thereby assure the air-powder mixture containing fine particles ofthe powder in a suitably dispersed state. The air-powder mixture withindispersion chamber 17 is diluted by the diluent air introduced thereintothrough second diluent air passage 20 and regulator holes 21A ofregulator 21. The thus diluted air-powder mixture then is dischargedfrom air-powder mixture outlet 18 into the user's oral cavity.

[0055] As be appreciated from the above explanation, the air-powdermixture flowing from powder receiving chamber 5 is diluted withinair-powder mixture reservoir 12 by the diluent air introduced intoair-powder mixture reservoir 12 through diluent air passage 19. A flowrate of the air-powder mixture is reduced within air-powder mixturereservoir 12 by the introduction of the diluent air. As a result, a partof the dose of the powder received within powder receiving chamber 5 issucked by one-time inhalation by the user. Therefore, the dose of thepowder received within powder receiving chamber 5 can be divided into aplurality of dose parts each being sucked by the user. Thus, the usercan suck a small amount of the powder that forms each dose part, byone-time inhalation. If it is required to deposit fine particulatemedicament having a small particle diameter in the bronchi or alveoli ofa patient, a dose of the medicament can be dispensed in parts which areinhaled by multiple-time inhalation of the user through the inhalator ofthe invention. The fine particulate medicament can be prevented frombeing deposited in the trachea and be stably deposited in the bronchi oralveoli by multiple-time inhalation of the dose parts. The inhalator ofthe invention can be effectively used for dispensing a dose of a powderor powder composition such as particulate medicament and powder tobacco,in parts by multiple-time inhalation.

[0056] Further, with the arrangement of second diluent air passage 20and regulator 21 for regulating the opening area of diluent air passage20, an amount of the diluent air introduced into dispersion chamber 17can be desirably regulated by axially moving regulator 21. A mixingratio between the powder and the air present in the air-powder mixturewithin dispersion chamber 17 can be readily controlled by the regulationof the diluent air to be introduced. Accordingly, an amount of thepowder which is sucked by one-time inhalation by the user, can bedesirably controlled using regulator 21 depending on the user's liking,kinds of particulate medicaments, or the like. This can improve aperformance of the inhalator. The amount of the powder for one-timeinhalation may be controlled by regulating the opening area at theconnection of upstream and downstream intake passages 7 and 8 of airintake path 6 or the opening area at the connection of discharge passage10 and connecting passage 11 of air-powder mixture path 9.

[0057] Furthermore, with the arrangement of dispersion passages 16 anddispersion chamber 17 at dispersion part 15, the swirl flow of theair-powder mixture can be produced within dispersion chamber 17, whichatomizes an aggregated mass of the powder remaining in dispersionchamber 17 and forms the air-powder mixture containing the powderparticles in a good dispersed state. This can improve a dispersionefficiency of the inhalator.

[0058] Further, upstream and downstream intake passages 7 and 8 of airintake path 6 is arranged to establish and block the fluid communicationbetween powder receiving chamber 5 and the outside of inhalator body 1.When the inhalator is in the nonuse position, upstream and downstreamintake passages 7 and 8 are disconnected from each other so that thefluid communication between powder receiving chamber 5 and the outsideof inhalator body 1 is blocked. In addition, discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 is arranged to allowand block the fluid communication between powder receiving chamber 5 andfirst air-powder mixture reservoir 12. In the nonuse position of theinhalator, discharge passage 10 and connecting passage 11 aredisconnected from each other so that the fluid communication betweenpowder receiving chamber 5 and first air-powder mixture reservoir 12 isblocked. With this arrangement of intake passages 7 and 8 and dischargepassage 10 and connecting passage 11, the powder received within powderreceiving chamber 5 can be prevented from flowing therefrom toward bothair intake inlet 7A and air-powder mixture reservoir 12 upon the usercarrying the inhalator. This can improve reliability of the inhalator.Further, when intake passages 7 and 8 are communicated with each otherupon using the inhalator, the opening area of the connection of intakepassages 7 and 8 can be regulated to control the flow amount of the airflowing into powder receiving chamber 5. Therefore, the amount of thepowder present in the air-powder mixture produced within powderreceiving chamber 5 can be adjusted. Similarly, upon communication ofdischarge passage 10 and connecting passage 11, the opening area of theconnection thereof can be regulated to control the flow amount of theair-powder mixture flowing from powder receiving chamber 5 intoair-powder mixture reservoir 12. The amount of the powder in theair-powder mixture flowing from air-powder mixture reservoir 12 towardair-powder mixture outlet 18 can be adjusted, and therefore, the amountof the powder to be sucked can be adjusted.

[0059] Although two air-powder mixture reservoirs 12 and 14 are providedwithin suction body 4 in this embodiment, a single air-powder mixturereservoir or three or more air-powder mixture reservoirs may beprovided.

[0060] In addition, a capsule chamber for storing a capsule having adose of the powder may be substituted for powder receiving chamber 5. Inthis case, the capsule within the capsule chamber may be pierced using apiercing device upon inhalation.

[0061] Further, a shutter member may be provided for blocking andallowing the fluid communication between powder receiving chamber 5 andthe outside of inhalator body 1 and air-powder mixture reservoir 12,instead of the arrangement of upstream and downstream intake passages 7and 8 of air intake path 6 and discharge passage 10 and connectingpassage 11 of air-powder mixture path 9. The shutter member may berotatably or slidably disposed within air intake path 6 extendingbetween powder receiving chamber 5 and air intake inlet 7A and theportion of air-powder mixture path 9 which extends between powderreceiving chamber 5 and air-powder mixture reservoir 12.

[0062] Furthermore, either one of the upstream end portion of capsulebody 2 and engaging tube portion 3A of cap 3 may have on the outercircumferential surface a groove circumferentially extending within apredetermined angular region. The other may have on the outercircumferential surface a projection engageable with the groove suchthat both capsule body 2 and cap 3 are rotatably moveable to each otherin the predetermined angular region. A similar circumferentiallyextending groove may be formed on either one of the outercircumferential surface of the downstream end portion of capsule body 2and the outer circumferential surface of engaging tube portion 4A ofsuction body 4, and a similar projection may be formed on the otherthereof. If the projections reach the respective ends of the grooves,the communication between upstream and downstream intake passages 7 and8 and the communication between discharge passage 10 and connectingpassage 11 will be established. In this case, counter marks 22 can beomitted.

[0063] Next, a powder composition for use with inhalators and a processfor administering the powder composition using inhalators, according tothe present invention, will be explained hereinafter.

[0064] The powder composition is suitable to be administered from anoral or nasal cavity for deposition in inside parts of the human body.The powder composition includes at least two kinds of fine particlesselected from a group consisting of a first kind of fine particle havingan aerodynamic mean particle diameter of not less than 7 μm, a secondkind of fine particle having an aerodynamic mean particle diameter of5-7 μm, a third kind of fine particle having an aerodynamic meanparticle diameter of 3-3 μm, a fourth kind of fine particle having anaerodynamic mean particle diameter of 1-3 μm, and a fifth kind of fineparticle having an aerodynamic mean particle diameter of not more than 1μm. The first kind of fine particle having the aerodynamic mean particlediameter of not less than 7 μm is deposited in an oral cavity orhypoglottis of a human body. The second kind of fine particle having theaerodynamic mean particle diameter of 5-7 μm is deposited in a throat ofa human body. The third kind of fine particle having the aerodynamicmean particle diameter of 3-5 μm is deposited in a trachea of a humanbody. The fourth kind of fine particle having the aerodynamic meanparticle diameter of 1-3 μm is deposited in bronchi of a human body. Thefifth kind of fine particle having the aerodynamic mean particlediameter of not more than 1 μm is deposited in alveoli of a human body.

[0065] Preferably, the fine particles of the powder composition of thepresent invention have a significantly narrow particle sizedistribution. More preferably, the fine particles have the particle sizedistribution consistent with a predetermined range of an aerodynamicmean particle diameter which is required for deposition in therespective parts of the human body.

[0066] The powder composition may be powder tobacco and particulatemedicament. The powder tobacco contains at least two kinds of fineparticles selected from the first, third and fifth kinds of fineparticles as described above. For instance, the powder tobacco maycontain fine particles as a gustatory component which have theaerodynamic mean particle diameter of 45-55 μm for deposition in theoral cavity or hypoglottis, fine particles as a stimulatory componentwhich have the aerodynamic mean particle diameter of 3-3 μm fordeposition in the trachea or throat, and fine particles as an agentwhich have the aerodynamic mean particle diameter of 0.5-2 μm fordeposition in the alveoli or bronchi. A coffee extract powder may beused for the fine particles as a gustatory component having theaerodynamic mean particle diameter of 45-55 μm. A menthol extract powdermay be used for the fine particles as a stimulatory component having theaerodynamic mean particle diameter of 3-5 μm. A nicotine extract powdermay be used for the fine particles as an agent having the aerodynamicmean particle diameter of 0.5-2 μm. If the powder tobacco is inhaledwith the inhalator, the same taste, stimulus and nicotinic effect asthose obtained by smoking can be obtained.

[0067] The particulate medicament as the powder composition of thepresent invention contains at least two kinds of fine particles selectedfrom the first through fifth kinds of fine particles as described above.The particulate medicament may contain fine particles as a gustatorycomponent which have the aerodynamic mean particle diameter of 60-80 μmfor deposition in the oral cavity or hypoglottis, fine particles as anantiphlogistic agent which have the aerodynamic mean particle diameterof 4-6 μm for deposition in the trachea or throat, and fine particles asan agent which have the aerodynamic mean particle diameter of 1-3 μm fordeposition in the alveoli or bronchi. A powdered troche or candy may beused for the fine particles as a gustatory component having theaerodynamic mean particle diameter of 60-80 μm. An antiphlogistic powdermay be used for the fine particles as an antiphlogistic agent having theaerodynamic mean particle diameter of 4-6 μm. An antibiotic powder maybe used for the fine particles as an agent having the aerodynamic meanparticle diameter of 1-3 μm.

[0068] In addition, the particulate medicament as the powder compositionof the present invention may be selected from an analgesic agent, ananginal preparation, an antiallergic agent, an anti-infective agent, anantihistaminic agent, an anti-inflammatory agent, an antitussive agent,a bronchodilator agent, a diuretic agent, an anticholinergic agent, andthe like, depending on cure purposes. These powder agents may havevarious aerodynamic mean particle diameters suitable for deposition indifferent target parts of the human body.

[0069] If required, the particulate medicament as the powder compositionof the present invention may be used together with a known excipientacceptable for inhalation into the human body. The composition of theparticulate medicament is prepared in accordance with the doctor'sprescription given on the basis of the patient's symptom.

[0070] In the administration process of the present invention, first thepowder composition is prepared so as to contain at least two kinds offine particles selected from the first to fifth kinds of fine particlesas described above. The at least two kinds of fine particles of thepowder composition may be blended together. The thus prepared powdercomposition is supplied to an inhalator suitable for dispensing a powderinto the human body. The powder composition may be capsulated and thenaccommodated in the inhalator. Subsequently, the powder compositionsupplied is discharged from the inhalator. If the above-describedinhalator of the present invention is used, the powder composition maybe dispersed within the inhalator and then discharged therefrom withoutaggregation of the fine particles of the powder composition.

[0071] The powder composition and administration process of the presentinvention can be suitably used for cure of multiple diseases using theparticulate medicaments which have effects on the multiple diseases,respectively. Specially, the powder composition and administrationprocess of the present invention is suitable for providing analgesia andcuring inflammation in the oral cavity and/or throat, asthma,bronchitis, COPD (chronic obstructive pulmonary disease), respiratorydisease such as thoracho-infection, and allergosis.

[0072] The inhalators useable in this embodiment are described inJapanese Patent Applications First Publication Nos. 62-41668 and9-47509, Japanese Patent Application Second Publication No. 63-6024, andU.S. Pat. No. 5,996,577.

EXAMPLES

[0073] The present invention is described in more detail by way ofexamples. However, these examples are only illustrative and not intendedto limit a scope of the present invention thereto.

Example 1

[0074] A dose of a powder tobacco was prepared by blending 5 mg ofcoffee extract particulates having an aerodynamic mean particle diameterof 50 μm, 10 mg of menthol extract particulates having an aerodynamicmean particle diameter of 4 μm, and 1 mg of nicotine extractparticulates having an aerodynamic mean particle diameter of 0.5-2 μmtogether. The thus prepared dose of a powder tobacco was supplied to asuitable inhalator as described above and then discharged from theinhalator.

Example 2

[0075] A dose of a particulate medicament mixture was prepared byblending candy particles having an aerodynamic mean particle diameter of70 μm, antiphlogistic agent particles having an aerodynamic meanparticle diameter of 5 μm, antibiotic agent particles having anaerodynamic mean particle diameter of 2 μm together in accordance with adoctor's prescription. The thus prepared dose of a particulatemedicament mixture was filled in a capsule. The thus capsulated dose ofa particulate medicament mixture was accommodated in a suitableinhalator as described above and then discharged from the inhalator.

[0076] Using the powder composition and the administration process ofthe present invention, a dose of the powder composition containing theat least two kinds of fine particulates different in mean particlediameter from each other can be selected depending on the target partsof the human body in which the powder composition is required to bedeposited, and can be deposited in the target parts by one-timeinhalation using the inhalator. Namely, multi-purpose dosage ofparticulate medicaments, for instance, deposition of the particulatemedicaments in both of the trachea and the alveoli or all of the throat,the bronchi and the alveoli, can be achieved during the one-timeinhalation.

[0077] Further, using the powder composition and the administrationprocess of the present invention, the patient can dispense with multipletimes of inhalation for dosing a plurality of particulate medicamentsrequired in different prescriptions. Also, any specific compound ofparticulate medicaments may not be required for multi-purposeprescription.

[0078] Furthermore, in a case where the capsulated powder composition ofparticulate medicaments having different mean particle diameters isused, the patient can dispense with adjusting the amount of the powdercomposition required for each inhalation and the mixing ratio of thedifferent kinds of particulate medicaments.

[0079] The entire contents of basic Japanese Patent Applications Nos.2000-363636 filed on Nov. 29, 2000, and 2000-359822 filed on Nov. 27,2000, inclusive of the specification, claims and drawings, are hereinincorporated by reference.

[0080] Although the invention has been described above by reference tocertain embodiments of the invention, the invention is not limited tothe embodiments described above. Modifications and variations of theembodiment described above will occur to those skilled in the art, inlight of the above teachings. The scope of the invention is defined withreference to the following claims.

What is claimed is:
 1. An inhalator for administering an air-powdermixture, comprising: an inhalator body including an air intake path forintroducing an air into the inhalator body, and an air-powder mixtureoutlet for discharging the air-powder mixture from the inhalator body; apowder receiving chamber adapted to receive a powder, the powderreceiving chamber being disposed within the inhalator body andcommunicated with an outside of the inhalator body through the airintake path; an air-powder mixture path adapted to transmit theair-powder mixture flowing from the powder receiving chamber to theair-powder mixture outlet; an air-powder mixture reservoir adapted totemporarily store the air-powder mixture flowing from the powderreceiving chamber, the air-powder mixture reservoir being disposedwithin the air-powder mixture path; and a diluent air passage adapted tointroduce a diluent air into the air-powder mixture reservoir, thediluent air passage communicating the air-powder mixture reservoir withthe outside of the inhalator body.
 2. The inhalator as claimed in claim1, further comprising a second diluent air passage adapted to introducea diluent air into the air-powder mixture path downstream of theair-powder mixture reservoir upon the air-powder mixture flowing fromthe air-powder mixture reservoir, and a regulator variably controllingan opening area of the second diluent air passage.
 3. The inhalator asclaimed in claim 1, further comprising a dispersion part adapted todisperse the powder in the air-powder mixture passing through theair-powder mixture path downstream of the air-powder mixture reservoir.4. The inhalator as claimed in claim 3, wherein the dispersion partcomprises a plurality of dispersion passages branched from theair-powder mixture path downstream of the air-powder mixture reservoir,and a dispersion chamber disposed within the air-powder mixture pathdownstream of the dispersion passages, each of the dispersion passageshaving an outlet passage portion that is open into the dispersionchamber and arranged to form a swirl flow of the air-powder mixture. 5.The inhalator as claimed in claim 4, wherein the dispersion chamber hasa generally circular-shaped section and the outlet passage portion ofeach of the dispersion passages extends in a tangential direction of thedispersion chamber.
 6. The inhalator as claimed in claim 1, wherein theair intake path is arranged to allow and block fluid communicationbetween the powder receiving chamber and the outside of the inhalatorbody.
 7. The inhalator as claimed in claim 6, wherein the air intakepath comprises at least two passages having an alignment position wherethe at least two passages are in alignment with each other and an offsetposition where the at least two passages are out of alignment with eachother.
 8. The inhalator as claimed in claim 1, wherein the air-powdermixture path is arranged to allow and block fluid communication betweenthe powder receiving chamber and the air-powder mixture reservoir. 9.The inhalator as claimed in claim 8, wherein the air-powder mixture pathcomprises at least two passages disposed between the powder receivingchamber and the air-powder mixture reservoir, the plurality of passageshaving an alignment position where the at least two passages are alignedwith each other and an offset position where the at least two passagesare offset from each other.
 10. The inhalator as claimed in claim 4,further comprising a second air-powder mixture adapted to temporarilystore the air-powder mixture flowing from the first air-powder mixturereservoir toward the dispersion passages of the dispersion part.
 11. Theinhalator as claimed in claim 10, wherein each of the dispersionpassages comprises an inlet open into the second air-powder mixturereservoir.
 12. An inhalator for administering an air-powder mixture,comprising: a casing including an air intake inlet for introducing anair into the casing, and an air-powder mixture outlet for dischargingthe air-powder mixture from the casing; powder receiving means forreceiving a powder within the casing and permitting the powder to beadmixed with the air introduced from the air intake inlet; air-powdermixture storing means for temporarily storing the air-powder mixturepassing through the powder receiving means; diluent air passage meansfor permitting a diluent air to flow into the air-powder mixture storingmeans; and air-powder mixture path means for permitting the air-powdermixture to flow from the powder receiving means to the air-powdermixture outlet via the air-powder mixture storing means.
 13. Theinhalator as claimed in claim 12, further comprising air intake pathmeans for permitting the air to flow from the air intake inlet into thepowder receiving means.
 14. The inhalator as claimed in claim 12,wherein the air-powder mixture path means allows and blocks fluidcommunication between the powder receiving means and the air-powdermixture storing means.
 15. The inhalator as claimed in claim 12, furthercomprising a second diluent air passage means for permitting a diluentair to flow into the air-powder mixture path means downstream of theair-powder mixture storing means upon the air-powder mixture flowingfrom the air-powder mixture storing means.
 16. The inhalator as claimedin claim 15, further comprising a regulator variably controlling anopening area of the second diluent air passage means.
 17. The inhalatoras claimed in claim 12, further comprising dispersion means forpreventing the powder in the air-powder mixture from being aggregatedtogether.
 18. The inhalator as claimed in claim 17, wherein thedispersion means comprises passages means for forming a swirl flow ofthe air-powder mixture and chamber means for receiving the swirl flow ofthe air-powder mixture.
 19. The inhalator as claimed in claim 18,wherein the chamber means has a generally circular-shaped section andthe passage means extends in a tangential direction of the chambermeans.
 20. A powder composition for use with an inhalator, comprising:at least two kinds of fine particles selected from a first kind of fineparticles having an aerodynamic mean particle diameter of not less than7 μm, a second kind of fine particles having an aerodynamic meanparticle diameter of 5-7 μm, a third kind of fine particles having anaerodynamic mean particle diameter of 3-5 μm, a fourth kind of fineparticles having an aerodynamic mean particle diameter of 1-3 μm, and afifth kind of fine particles having an aerodynamic mean particlediameter of not more than 1 μm.
 21. The powder composition as claimed inclaim 20, wherein the powder composition comprises powder tobacco. 22.The powder composition as claimed in claim 20, wherein the powdercomposition comprises particulate medicament.
 23. A process foradministering a powder composition using an inhalator, comprising:preparing the powder composition containing at least two kinds of fineparticles selected from a first kind of fine particles having anaerodynamic mean particle diameter of not less than 7 μm, a second kindof fine particles having an aerodynamic mean particle diameter of 5-7μm, a third kind of fine particles having an aerodynamic mean particlediameter of 3-5 μm, a fourth kind of fine particles having anaerodynamic mean particle diameter of 1-3 μm, and a fifth kind of fineparticles having an aerodynamic mean particle diameter of not more than1 μm; supplying the powder composition to the inhalator; and dischargingthe powder composition from the inhalator.
 24. The process as claimed inclaim 23, wherein the discharging comprises dispersing the powdercomposition within the inhalator.
 25. The process as claimed in claim23, further comprising capsulating the powder composition.
 26. Theprocess as claimed in claim 23, wherein the powder composition comprisespowder tobacco.
 27. The process as claimed in claim 23, wherein thepowder composition comprises particulate medicament.